Filters with different filter elements are used for cleaning water with solid particles in suspension, the packs being formed with superimposed rings or disks which produce the best results, above all for removing very fine particles.
Many patents using cartridge filters with differently grooved annulus-shaped rings are known. The Spanish Utility model ES1040967U thus mentions rings with uniformly laid out grooves inclined on one of their faces. The Spanish Utility models ES1050263U and ES1055543U describe a ring grooved on both faces. Patent GB 2147516A presents a pack of rings formed by means of a helical strip. EP 1308195A1 describes a perforated-disk based filter system. U.S. Pat. No. 4,740,302(A) relates to a filter with a filter pack formed by extruded U-shaped rings and passage through microchannels. The Spanish Patent ES2277792 divides the dirt by diameters in different places according to the different filtration phases, which represents a significant advantage which delays clogging time. The last phase of the filter indicated in this patent comprises a pack of rings, but the configuration thereof is not shown.
The problems of these systems having a single filtration phase increases when the water is very dirty since the rapid clogging of the filter pack in its filtration area means that there is no practical filtering time and all the flow is used for the necessary consecutive washings. This reduces the performance of the filter, greatly increasing the water drained in the washing. This problem is dealt with by the present invention which separates dirt by diameters in different areas of the filter pack, the time between washes and the filtration performance being increased, in addition to other improvements, as will be indicated throughout the following description.